A plastic spectacle lens, which is one of optical lenses, is provided with performance requested of the spectacle lens by performing various coating processes on its surface. These coating processes include a primer process, a process of forming a hard coat film, and a process of forming an antireflection film.
A primer film formed by the primer process has a function of adding performance including shock resistance, adhesion, and crack mitigation using softness. A hard coat film needs to be very hard in order to improve scratch resistance. An outermost layer serving as the outer surface of the hard coat film is provided with an antireflection film. By arranging the antireflection film on the outermost layer, performance including the antireflection function, durability, and scratch resistance is further added.
A primer layer at the time of the primer process and a hard coat layer serving as a hard coat film are formed by applying a coating solution to a lens surface. As a method of applying a coating solution to a lens surface, there are a dipping method, a spin coat method, a spray coat method, and an inkjet method as disclosed in patent literature 1. Application of a coating solution by the inkjet method disclosed in patent literature 1 is performed so that a spectacle lens substrate is rotated in a state in which the lens surface is directed vertically to uniform the film thickness on the entire lens surface.
The film thickness is uniformed by dividing the lens surface into a plurality of concentric coating regions, and adjusting the amount of coating solution for the respective coating regions. On the lens surface of a spectacle lens, interference fringes sometimes appear in a state in which various above-mentioned films are formed. It is known that the interference fringes are reduced by forming a thick hard coat film.
The coating solution applied to the lens surface is cured by a curing apparatus. A thermosetting coating solution is heated and cured by the curing apparatus. An ultraviolet curing coating solution is irradiated with ultraviolet rays and cured by the curing apparatus.